1. Field of the invention:
The present invention relates to the field of systems for controlling high pressure flows, particularly in containing and extinguishing oil and gas well fires.
2. Statement of the problem:
A problem of great concern in high pressure flow of fluid materials is in the control of such pipelines once flow has commenced. This is particularly of concern in the exploitation of energy sources such as oil and gas, due to the danger of high pressure blowouts and/or fires. The occurrence of a blowout or fire creates immediate risk of human safety, potentially enormous harm to the environment, great financial expense and loss of valuable energy resources.
There have been a number of prior attempts to control these blowouts. These are typically of two types. The first type require installation of control systems prior to the blowout occurring. Examples of these are blowout preventers which are stacked above the well casing and are designed to smash, pinch and scissor the drill pipe to hopefully close off the flow through the pipe. Also used are "Hydril" apparatus which are designed to close off the area around the drill pipe to prevent loss of the flow.
Other approaches include system as disclosed by Poole in U.S. Pat. No. 4,316,506, issued Feb. 23, 1982. This system injects a mixture of chemicals and gases into the flow of hydrocarbons in the drill pipe which are less flammable. Also issued to Poole in U.S. Pat. No. 4,899,827 is a system for injecting water as well.
U.S. Pat. No. 3,870,098, issued to Houston, discloses a remotely controllable subterranean oil well valve for sealing the pipe in the event of a fire or blowout. This device requires prior installation and shears the pipe to close it off should a fire or blowout occur. It may be possible to allow some regulated flow through the pipe by control of the shearing mechanism.
U.S. Pat. No. 4,553,589 issued to Jennings et al. discloses a subsurface safety valve control line which operates a subsurface valve to shut off the flow through the pipe should a fire or blowout occur.
U.S. Pat. No. 3,887,011 issued to Dokes et al. discloses a fire extinguisher system which uses a series of pipes and valves which are activated by the melting of an element in the case of fire to divert the flow to the atmosphere.
All of these systems require installation prior to a fire or blowout occurring. None are able to be installed once a fire or blowout has occurred. The only known approaches to containment after a fire or blowout has occurred requires the use of explosives to extinguish the flame and the dropping of heavy materials on the blowout to smother the flow and fire. These approaches are quite dangerous and are often ineffective in high pressure situations.
Therefore, a need exists for a system for containing oil and gas well fires as well as for controlling high pressure flow, especially from subterranean sources.
3. Solution to the problem:
The present invention solves these and other problems. The present invention provides a system for controlling high pressure flows of fluid material.
The system of the present invention has particular utility in extinguishing oil and gas well fires.
The system of the present invention can be installed after the fire or blowout has already began.
The present invention provides a system that can be installed with relatively little danger to human safety.
The present invention provides a system that can be used to control high pressure flows.
The present invention provides a system that can be installed on existing systems as well as new systems.
The present invention provides a system that enables surface facilities to be quickly repaired and production resumed.
These and other features of the invention will be evident from the ensuing description taken in conjunction with the drawings.